The creation of FORTRAN, which debuted in 1957, marked a significant stage in the development of computer-programming languages. Previous programming was written in machine (first-generation) language or assembly (second-generation) language, which required the programmer to write instructions in binary or hexadecimal arithmetic. Frustration with the arduous nature of such programming led Backus to search for a simpler, more accessible way to communicate with computers. During the three-year development stage, Backus led an eclectic team of 10 International Business Machines (IBM) employees to create a language that combined a form of English shorthand with algebraic equations.

FORTRAN enabled the rapid writing of computer programs that ran nearly as efficiently as programs that had been laboriously hand coded in machine language. As computers were rare and extremely expensive, inefficient programs were a greater financial problem than the lengthy and painstaking development of machine-language programs. With the creation of an efficient higher-level (or natural) language, also known as a third-generation language, computer programming moved beyond a small coterie to include engineers and scientists, who were instrumental in expanding the use of computers.

By allowing the creation of natural-language programs that ran as efficiently as hand-coded ones, FORTRAN became the programming language of choice in the late 1950s. It was updated a number of times in the 1950s and 1960s in order to remain competitive with more contemporary programming languages. FORTRAN 77 was released in 1978, followed by FORTRAN 90 in 1991 and further updates in 1996 and 2004. However, fourth- and fifth-generation languages largely supplanted FORTRAN outside academic circles beginning in the 1970s.